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Scientists at Stanford develop water splitter that runs on ordinary AAA battery

news.stanford.edu

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Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#51

Post by lutorm »

epistasis wrote: post #48
lutorm wrote: post #38

Earlier quoted context omitted.

It is anything but. It's like saying "gasoline is emissions free, it's the burning of it that's the problem." If we're going to have a rational discussion about various forms of emission, we need to talk about total fuel cycle emissions, otherwise it's meaningless. Touting one small section of a fuel cycle as emissions free is at best confusing, at worst misleading.

You're still being incredibly dishonest, and if you're willing to talk like that, you should really worry about how much it hurts your personal credibility. With gasoline, the use of stored energy requires emissions. With batteries, the use of stored energy does not require emissions. You are creating false equivalencies, the only purpose of which is to drag down the discussion and stop the discussion. You want to ta…

Tone down the hyperbole a bit there.

With gasoline, the use of stored energy requires emissions.

With batteries, the production of stored energy required emissions.

True, the analogy isn't perfect, because maybe the batteries were charged from a PV system (though in practice chances are they were not) but to call it "incredibly dishonest" and "blatantly false" seems a bit excessive, don't you think?

The point is, while using power from a battery doesn't cause any emissions, you need to know where the energy came from to make any meaningful comparisons.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#52

Post by jack-r-abbit »

dang wrote: post #49
lutorm wrote: post #39

Earlier quoted context omitted.

Give me a break. Did you read the article? Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas, a fossil fuel that contributes to global warming. Now scientists at Stanford University have developed a low-cost, emissions-free device that uses an ordinary AAA battery to produce hydrogen by water electrolysis. You don't agree the juxtaposition gives the impression tha…

> Give me a break. Did you read the article? Please don't be personally rude on Hacker News. This comment would be fine without the first two sentences.

No disrespect... but nardi did, in fact, NOT read the article: https://news.ycombinator.com/item?id=8213612

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#53

Post by lutorm »

dang wrote: post #49
lutorm wrote: post #39

Earlier quoted context omitted.

Give me a break. Did you read the article? Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas, a fossil fuel that contributes to global warming. Now scientists at Stanford University have developed a low-cost, emissions-free device that uses an ordinary AAA battery to produce hydrogen by water electrolysis. You don't agree the juxtaposition gives the impression tha…

> Give me a break. Did you read the article? Please don't be personally rude on Hacker News. This comment would be fine without the first two sentences.

Guilty, though I responded to the OPs "I'm amazed at the ignorance in these comments". You don't think that warrants the same comment?

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#54

Post by yongjik »

epistasis wrote: post #48
lutorm wrote: post #38

Earlier quoted context omitted.

It is anything but. It's like saying "gasoline is emissions free, it's the burning of it that's the problem." If we're going to have a rational discussion about various forms of emission, we need to talk about total fuel cycle emissions, otherwise it's meaningless. Touting one small section of a fuel cycle as emissions free is at best confusing, at worst misleading.

You're still being incredibly dishonest, and if you're willing to talk like that, you should really worry about how much it hurts your personal credibility. With gasoline, the use of stored energy requires emissions. With batteries, the use of stored energy does not require emissions. You are creating false equivalencies, the only purpose of which is to drag down the discussion and stop the discussion. You want to ta…

Your statement would make sense if somewhere there is a vast reserve of charged batteries buried deep underground which we are mining, transporting, and putting on each car.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#55

Post by seanflyon »

cjensen wrote: post #32
crististm wrote: post #21

Earlier quoted context omitted.

I don't know about ignorance, but basically, the energy you get from splitting the water molecule (in the form of H2 and O2) is lower than the energy consumed to make the split. For storage you will also have to deeply freeze the gases unless you want to have huge tanks for storage So what makes a hydrogen exposed freezing tank better suited for transport and storage than a chemical battery?

A car which runs on hydrogen can be refueled in a few minutes. Batteries need an hour of charge or a battery swap which costs labor.

A battery swap only costs labor if you do it manually. I don't see why you would do that.

http://www.youtube.com/watch?v=H5V0vL3nnHY

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#56

Post by seanflyon »

nardi wrote: post #28
lutorm wrote: post #24

Earlier quoted context omitted.

Well, if they claimed that using batteries was "emissions free", I would complain about that, too. With hydrogen, the issue issue is that (at least to my understanding) if you have electricity, we already have a far more efficient solution: put the electricity directly into a battery and use it to power a motor. Going the route over electrolysis->hydrogen storage->fuel cell imposes such efficiency penalties that it w…

Hey, I like chemical batteries too, but they're not capacitors. You don't put electricity into them. You drive an electrochemical reaction with them, which is subject to its own inefficiencies, as well as wear and tear on the battery, which isn't a problem with hydrogen fuel cells. Hydrogen fuel cells also tend to be highly efficient.

> wear and tear on the battery, which isn't a problem with hydrogen fuel cells.

Sadly this is not the case. Fuel cells have similar lifespans as batteries.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#57

Post by justin66 »

jacquesm wrote: post #36
justin66 wrote: post #25

Earlier quoted context omitted.

> ... and not a single word about how the necessary electricity needed to make this "zero emission fuel" is supposed to be produced. At some point you have to trust the reader to understand things that are completely obvious. That's a necessary quality of good writing, even if you're adhering to the newspaper standard of targeting someone at the 8th grade reading level.

But in the case of Hydrogen such 'completely obvious' things are actually not all that obvious to the target audience. So it's ok to spell it out to avoid the risk of overselling a new technology and thus create a situation where it will fail to deliver due to unrealistic expectations. Hydrogen is not exactly the easiest compound to work with and how it is generated is a huge part of equation.

The article did not claim the energy used to proceed the hypothetical AAA battery was free. That certainly would oversell some things.

On the contrary, if they'd demoed the thing with a small solar panel I might have had some issues with it, and wanted to see some elaboration. The fundamentally good thing about the battery example is that everyone understands that making a battery costs something. IMO it's a better example than you give them credit for.

Certainly everyone reading here understands that it takes energy to make a battery, that the creators of the gadget haven't defeated the laws of thermodynamics, and so on. Hence my comment about trusting the reader.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#58

Post by nardi »

jack-r-abbit wrote: post #52
dang wrote: post #49

Earlier quoted context omitted.

> Give me a break. Did you read the article? Please don't be personally rude on Hacker News. This comment would be fine without the first two sentences.

No disrespect... but nardi did, in fact, NOT read the article: https://news.ycombinator.com/item?id=8213612

I meant I hadn't read the paper. I had of course read the linked article, which is light on details of how they created the catalyst.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#59

Post by lutorm »

jacquesm wrote: post #33
nardi wrote: post #26

Earlier quoted context omitted.

Ignorance. The news here isn't "we discovered electrolysis!" It's "we developed a new, efficient, and cheap electrocatalyst!" Did you do that when you were 9 too?

Actually, the kids chemistry book that I read as a 10 year old or so had a very clear picture in it of one of the electrodes made of a guilder (dutch coin at the time) and noted it worked better than other coins because of its high nickel content. That may have been coincidence but it certainly wasn't new knowledge to me that Nickel works well as an electrode when splitting water in Hydrogen and Oxygen. I wished I'd…

We must have had a similar childhood! :-)

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#60

Post by jack-r-abbit »

nardi wrote: post #58
jack-r-abbit wrote: post #52

Earlier quoted context omitted.

No disrespect... but nardi did, in fact, NOT read the article: https://news.ycombinator.com/item?id=8213612

I meant I hadn't read the paper . I had of course read the linked article, which is light on details of how they created the catalyst.

My bad. When you said article, I thought you meant the linked article. I don't see any reference to a paper so clearly I have no idea what you are talking about. I'll just go about my day. :)
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